How to Use Experimental Evidence in English Patent Litigation

Experimental evidence can play a valuable role in patent litigation. It is not uncommon in patent validity proceedings for an expert will say to they would, when presented with a piece of prior art, have conducted a particular experiment in order to progress the research. Without then conducting the actual experiment that they said they would have done, it is impossible to know what the result of that experiment would have been. Knowing the result of that experiment is sometimes critical to a case, such as when the defendant argues the patent is invalid due to lack of novelty or inventive step or indeed sufficiency.

Experimental evidence is also frequently needed to ascertain the fact of whether or not an allegedly infringing product falls within the claims of a patent. For example, are the particle sizes of the allegedly infringing product within the range specified in the patent? Is
there any of the infringing product in the mixture being marketed? Unless the opposing party is prepared to admit the fact in question, the party asserting the fact will need to prove it by experiment.